Re: [Qemu-devel] [PATCH] exec.c: Fix subpage memory access to RAM MemoryRegion

[Andreas Färber]

Am 29.11.2011 15:00, schrieb Avi Kivity:
> On 11/29/2011 02:47 PM, Andreas Färber wrote:
>>>  
>>>      addr += mmio->region_offset[idx];
>>>      idx = mmio->sub_io_index[idx];
>>> +    if (unlikely(idx == IO_MEM_RAM)) {
>>> +        ram_addr_t raddr = /*mmio->base |*/ addr;
>>> +        void *ptr = qemu_get_ram_ptr(raddr);
>>
>> ...and/or this seems to lead to "Bad RAM pointer" (or so) when there's
>> ELF code loaded into the subpage at that address despite being IO_MEM_RAM?
>> (Seen, e.g., if for RL78 I increase the page size from 12 to 16.)
>>
> 
> addr is relative to the start of the page, instead of the start of the
> region.  You can use mmio->region_offset[idx] to compensate.

That's exactly what the first line of the snippet above does, no?
(sorry, there's still a confusing comment from an earlier attempt)

Andreas

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